Tubing



Oct. 11, 1932. R, H 1,881,610

TUBING Filed July 11, 1930 I N V EN TOR. ROLL/NM HYDE,

Patented Oct. l1, 1932 UNITED STATES PATENT OFFICE HYDE, OF DETROIT,MICHIGAN,

30mm x.

. 00., OF DETROIT, MICHIGAN,

TUBING This invention relates to tubing and more particularly to tubingadapted for use in transferring heat in heating, cooling, refrigeratingand ventilating devices and mstallations.

One object of my invention is to provide a tubing, whether seamless orotherwise, w1t h heat conducting fins extending long1tud1- nally oraxially of the tubing and connected with or carried by the exterior wallthereof to conduct heat either to or fromsaid wall, depending on whetherthe fins are internal fins projecting into the tubing or external finsextending outside of the tubing.

Another object of my invention is to have the internal fins formed byextending inward portionsof the metal constitutin the outer wall of thetube so that the fins wlll be integrally connected with said wall tomore efliciently conduct heat to or from the same.

A further object of my invention is to have the fins extend into thetube in such manner as to not only divide or separate the body of thefluid within the tube into smaller sections for contact with the fins,but also to considerably increase the inner surface of the tube wall incontact with the fluid to facilitate a more rapid transfer of heat toand from the same than possible with a tube with a plain bore orpassage.

A further object of my invention is to provide in a loc -seam tube theinternal fins by folding the metal of the tube wall to provide the finsin the making of the tube.

The invention consists further in the matters hereinafter described andclaimed.

In the accompanying drawing:

Fig. 1 is an end view of a seamless tube with internal fins constructedin accordance with my invention;

Fig. 2 is a side view of the tube with a portion broken away to showthat the fins extend longitudinally of the tube;

Fig. 3 is an end view of the tube of my invention showing external finsinserted in the pockets formed bythe internal fins;

Fig. 4 is a side view of the structure shown in Fig. 3 to show that theexternal fins also extend longitudinally of the tube;

Fig. 5 is an end view of a tube of my in- Application filed July 11,1980. Serial No. 487,328.

fins may be extended into the interior of the preferably disposed toextend lengthwise of a the tube. The tube may be of the seamless type,in which case the internal fins are formed by drawing the tube through asuitable die. On the other hand, the tube may be of the lock-seam type,tube is formed from a. strlp of the desired sheet metal with the finsfolded from the metal sheet and extending into the interior of the tube.In this type, the lock seam for the tube .is provided along th of one ofthe internal fins where the edges of'the sheet metal strip meet or cometogether.

In Figs. 1 and 2 of the drawing, I have shown my invention applied to aseamless tube, in which 1 indicates the outer wall of the tube and 2 theinternal fins. The fins are formed by extending inward portions of theouter wall 1 to the extent desired. In Figs.

1 and 2, the fins 2 extend into the tube to substantially the sameextent, and when the tube is round or cylindric, the fins may beradially disposed with respect to the center or axis of the tube. It isto be understood, however,

that any other arrangement for the fins may be adopted without departingfrom the spirit and scope of my invention. In forming the fins 2 byprojecting inward integral portions of the wall 1, each fin comprises apair of substantially parallel inwardly extending wall portions 3, 3,integrally connected by the fold in the metal at the inner end of thefin and similarly connected with the outer wall 1 at the bend or turn inthe metal as shown in Fig. 1. The fins 2 so formed ex- I8 my invention,I so form with and extended into in which case the 70 e inner edge 75 Ii tend longitudinally or axially of the tube throughout the entirelength thereof, and after the tube has been formed, it is cut intosections tothe lengths desired.

Forming the fins 2 in the manner described provides spaces or pockets 4between each pair of fin sections 3, 3, and which pockets extendlongitudinally of the tube and open outwardly through the outer surfacethereof, as shown in Fig. 2. These pockets 4 could be closed .as bypressing the wall sections 3, 3 together in the making of the tube orleft open for the entrance of the media in which the tube is located toaid in the transfer of heat to or from the liquid or gas contained in orflowing through the tube. The pockets also provi e means wherebyexternal fins may be readily, attached to the tube.

These fins are referably made in the form of flat stri s of t e desiredsheet metal or other materia and are of a width to fit suflicientlytight in the pockets to secure the fins to the tube. In "Fig. l I haveindicated one of these external fins in dotted lines by 5. In Fig. 3, Ihave shown the external fins in full lines,

and it will be noted from Fig. 4 that these fins extend lengthwise ofthe tube. They may be either in continuous strips or in sec tions as maybe desired, according to the nature of the installation in which thetubing is employed. 'To prevent any possibility of the external fins 5dropping out of the pockets, they may be soldered in same.

In Figs. 3 to 6 I show my invention applied to a tube 1 of the lock-seamtype. When of this type, the tube is made from a strip of the desiredsheet metal and the internal fins 2- are formed by folding the metalstri on itself to provide the fins. When the tube is round, as shown inthe drawing, the internal fins 2 may be radially dispose the same asbefore. The seam of the tube w ere the edges of the sheet metal stripcome together are overlapped and interlocked as at 6 along the inneredge of one of the internal fins, as

shown in Figs. 3 and 5.

Instead of external fins in the form of strips 5, 5 as heretoforedescribed, I may provide the tube with external fins either in spiralform or in individual disk form. The tube after being produced with itsinternal fins is then run through a machine designed for the purpose ofapplying either the spiral fin or the individual disk fins which extendaround the tube and are arranged generally transverse to thelongitudinal axis thereof.

In Figs. 5 and 6, I'have shown a spiral fin 7 provided on the exteriorof the tube, and surrounding the tube from end to end thereof, orthroughout such portion or portions which are to be provided with suchfins.

The internal fins greatly increase the surface on the inside of thetube, and by forming the fins of the same piece of which the outer wallof the tube is formed, greater heat transfer is obtained as there is noheat loss, as would occur if the fins were made of separate pieces. Withthe internal fins longitudinal of the tube, the fins extend in an upwarddirection when the tube is vertical, and thus follow the direction ofthe conduction of heat to air. The interrfal fins present more surfaceto the gas or liquidto be cooled than provided by a tube with a plainbore, and thus provide for a greater transfer of heat. In leaving theinternal fins open at their outer ends, I not only provide pockets forthe longitudinal external fins, but bring such fins into direct contactwith a greater amount of direct surface on both sides of the externalfin, which further tends to increase the heat flow. When the tube isused without external. fins or used with external fins which extendaround or outside of the tube as when in indi vidual disk or spiralform, the pockets at the internal fins allow for the heat absorbedthereby to flow out into the open air or other media in which the tubemay be employed. The internal finsnot only provide an increased surfaceon the inside of the tube for, contact with the gas or liquid flowingthrough or contained in the tube, but also divide t e gas or liquid intoa multiplicity of relatively narrow sections lengthwise of the tube, andthus bring a greater portion of the'medium withinthe tube into contactwith theinternal fins for the transfer of heat to or through the same asthe case may be, depending on whether the tube is used for dissipatingheat from the content of thetube or applying heat thereto.

The tube of my invention is particularly applicable in the heating andventilating field, the refrigerating field, and, in fact, any fieldwhere heat transfer is dealt with. The tubes may be connected tosuitable headers or manifolds in the same manner as now employed withplain tubes.

The details of structure shown and described may be variously changedand modified without departing from the spirit and scope of myinvention.

I claim as my invention:

1. A tube of the character described having an outer wall, said outerwall having portions at a number of places about the axis of the tubeextended inward to provide internal fins for the tube, and external finsapplie to the outer wall and extending around aboui the same.

2. A tube of the character described, hav ing an outer wall made from astrip of shee' material, said strip being folded longitudi nally onitself to provide internal fins with in the tube when the strip is bentinto tub form, the meeting edges'of the strip being at and forming theinner edge of one of th internal fins and there being interlocked'tprovide the seam for the tube.

3. A tube of the character described hav ing an outer wall, said wallhaving portions at a number of places about the axis of the tubeextended inwardly to provide internal fins for the tube, said finsextending longitudinally-of the tube and each having the op- I positeside portions thereof in spaced relation to provide pockets openingthrough the outer surfaoe of the tube along the length of the same, andflat strips inserted in said pockets and extending outwardly from thetube along the same to provide external fins there-- for, said stripsbeing substantially as wide as the pockets. 4. A tube of the characterdescribed having an outer wall, said wall having portions 4 at a numberof places about the axisvof the tube extended inwardly toprovide'internal fins for the tube, and extending longitudinallythereof, and a substantially fiat strip wound spirally about the tube inedgewise relation thereto and extending outward from the tube to provideexternal fins for the tube.

In testimony whereof I affix my signature.

' ROLLIN M. HYDE.

